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Foliar-applied postemergence applications of glufosinate are often applied to glufosinate-resistant crops to provide nonselective weed control without significant crop injury. Rainfall, air temperature, solar radiation, and relative humidity near the time of application have been reported to affect glufosinate efficacy. However, previous research may have not captured the full range of weather variability to which glufosinate may be exposed before or following application. Additionally, climate models suggest more extreme weather will become the norm, further expanding the weather range to which glufosinate can be exposed. The objective of this research was to quantify the probability of successful weed control (efficacy ≥85%) with glufosinate applied to some key weed species across a broad range of weather conditions. A database of >10,000 North American herbicide evaluation trials was used in this study. The database was filtered to include treatments with a single postemergence application of glufosinate applied to waterhemp [Amaranthus tuberculatus (Moq.) Sauer], morningglory species (Ipomoea spp.), and/or giant foxtail (Setaria faberi Herrm.) <15 cm in height. These species were chosen because they are well represented in the database and listed as common and troublesome weed species in both corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] (Van Wychen 2020, 2022). Individual random forest models were created. Low rainfall (≤20 mm) over the 5 d before glufosinate application was detrimental to the probability of successful control of A. tuberculatus and S. faberi. Lower relative humidity (≤70%) and solar radiation (≤23 MJ m−1 d−1) on the day of application reduced the probability of successful weed control in most cases. Additionally, the probability of successful control decreased for all species when average air temperature over the first 5 d after application was ≤25 C. As climate continues to change and become more variable, the risk of unacceptable control of several common species with glufosinate is likely to increase.
Foliar-applied postemergence herbicides are a critical component of corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] weed management programs in North America. Rainfall and air temperature around the time of application may affect the efficacy of herbicides applied postemergence in corn or soybean production fields. However, previous research utilized a limited number of site-years and may not capture the range of rainfall and air temperatures that these herbicides are exposed to throughout North America. The objective of this research was to model the probability of achieving successful weed control (≥85%) with commonly applied postemergence herbicides across a broad range of environments. A large database of more than 10,000 individual herbicide evaluation field trials conducted throughout North America was used in this study. The database was filtered to include only trials with a single postemergence application of fomesafen, glyphosate, mesotrione, or fomesafen + glyphosate. Waterhemp [Amaranthus tuberculatus (Moq.) Sauer], morningglory species (Ipomoea spp.), and giant foxtail (Setaria faberi Herrm.) were the weeds of focus. Separate random forest models were created for each weed species by herbicide combination. The probability of successful weed control deteriorated when the average air temperature within the first 10 d after application was <19 or >25 C for most of the herbicide by weed species models. Additionally, drier conditions before postemergence herbicide application reduced the probability of successful control for several of the herbicide by weed species models. As air temperatures increase and rainfall becomes more variable, weed control with many of the commonly used postemergence herbicides is likely to become less reliable.
Where and under what conditions the transfer of energy between electromagnetic fields and particles takes place in the solar wind remains an open question. We investigate the conditions that promote the growth of kinetic instabilities predicted by linear theory to infer how turbulence and temperature-anisotropy-driven instabilities are interrelated. Using a large dataset from Solar Orbiter, we introduce the radial rate of strain, a novel measure computed from single-spacecraft data, which we interpret as a proxy for the double-adiabatic strain rate. The solar wind exhibits high absolute values of the radial rate of strain at locations with large temperature anisotropy. We measure the kurtosis and skewness of the radial rate of strain from the statistical moments to show that it is non-Gaussian for unstable intervals and increasingly intermittent at smaller scales with a power-law scaling. We conclude that the velocity field fluctuations in the solar wind contribute to the presence of temperature anisotropy sufficient to create potentially unstable conditions.
Background: Identification and timely reporting of multi-drug resistant organisms (MDROs) drives efficacy of infection prevention efforts. Data on MDRO reporting timeliness and inter-facility variability are limited. Facility-dependent variability in MDRO reporting across Tennessee was examined to identify opportunities for MDRO surveillance improvement. Methods: Data for reported Tennessee MDROs including carbapenem-resistant Enterobacterales (CRE), carbapenem-resistant Acinetobacter baumannii (CRAB), Carbapenem-resistant Pseudomonas aeruginosa (CRPA) and Candida auris, were obtained from the southeast regional Antibiotic Resistance Laboratory Network (ARLN) from 2018-2022, excluding screening and colonization specimens. Variance in days accrued from specimen collection to ARLN receipt was analyzed using one-way analysis of variance (ANOVA) with Tukey’s test (SAS 9.4). Facilities were categorized as fast (1-10 days), slow (11-20 days), or delayed (21-100 days) reporters. Results: There were 9,569 MDRO isolates reported. CRPA was reported faster than other MDROs (p < 0.001), while specimens from West Tennessee compared to other regions (p < 0.001) (Figure) and blood cultures compared to other specimens were reported more slowly (p < 0.001) (Table). There was no difference in reporting times for facilities using on-site microbiology laboratories versus reference laboratories (P = 0.062). Conclusion: MDRO reporting times varied across Tennessee by region, specimen, and organism. Future work to elucidate drivers of variability will consist of surveys and focused interviews with laboratory personnel to identify shared and unique barriers and opportunities for improvement.
Humanitarian crises and armed conflicts lead to a greater prevalence of poor population mental health. Following the 1 February 2021 military coup in Burma, the country's civilians have faced humanitarian crises that have probably caused rising rates of mental disorders. However, a dearth of data has prevented researchers from assessing the extent of the problem empirically.
Aims
To better understand prevalence of depressive and anxiety disorders among the Burmese adult population after the February 2021 military coup.
Method
We fielded an online non-probability survey of 7720 Burmese adults aged 18 and older during October 2021 and asked mental health and demographic questions. We used the Patient Health Questionnaire-4 to measure probable depression and anxiety in respondents. We also estimated logistic regressions to assess variations in probable depression and anxiety across demographic subgroups and by level of trust in various media sources, including those operated by the Burmese military establishment.
Results
We found consistently high rates of probable anxiety and depression combined (60.71%), probable depression (61%) and probable anxiety (58%) in the sample overall, as well as across demographic subgroups. Respondents who ‘mostly’ or ‘completely’ trusted military-affiliated media sources (about 3% of the sample) were significantly less likely than respondents who did not trust these sources to report symptoms of anxiety and depression (AOR = 0.574; 95% CI 0.370–0.889), depression (AOR = 0.590; 95% CI 0.383–0.908) or anxiety (AOR = 0.609; 95% CI 0.390–0.951).
Conclusions
The widespread symptoms of anxiety and depression we observed demonstrate the need for both continuous surveillance of the current situation and humanitarian interventions to address mental health needs in Burma.
The impact of Indigenous populations on historical fire regimes has been controversial and beset by mismatches in the geographic scale of paleofire reconstructions and the scale of land-use behaviors. It is often assumed that anthropogenic burning is linearly related to population density and not different cultural practices. Here we take an off-site geoarchaeology strategy to reconstruct variability in historical fire regimes (<1000 years ago) at geographic scales that match the archaeological, ethnohistorical, and oral tradition evidence for variability in the intensity of Indigenous land use by two different cultural groups (Ancestral Pueblo and Western Apache). We use multiple, independent proxies from three localities in ponderosa pine (Pinus ponderosa) forests in east-Central Arizona to reconstruct fire regime variability during four phases of cultural use of different intensities. Elevated charcoal with domesticate pollen (Zea spp.) but otherwise unchanged forest pollen assemblages characterized intensive land use by Ancestral Pueblo people during an early phase, suggesting fire use to support agricultural activities. By contrast, a phase of intensive pre-reservation Western Apache land use corresponded to little change in charcoal, but had elevated ash-derived phosphorus and elevated grass and ruderal pollen suggestive of enhanced burning in fine fuels to promote economically important wild plants.
We examine whether state judicial selection methods influence people’s evaluations of US Supreme Court nominees. We find that people from appointing states use nominee characteristics in their evaluations differently than people in electing states. Those from appointing states appear to be more concerned with traditional legal factors, while people from electing states appear to be slightly less concerned with them. Although the importance varies from characteristic to characteristic, state judicial selection system has a broad role in shaping how people evaluate judicial nominees. These findings counsel further research on judicial institutions and the public’s expectations of judges.
We examine whether the public evaluates Supreme Court nominees on the basis of judicial philosophies when presented with a description of those philosophies. Employing a conjoint experiment, we find that the public will evaluate nominees’ judicial philosophies as well as the nominees’ partisanship, ideology, and qualifications. We also discover significant differences between Republicans and Democrats. These results have important implications for the future of judicial nominations, framing, and public support for the judiciary.
COVID-19 vaccines are likely to be scarce for years to come. Many countries, from India to the U.K., have demonstrated vaccine nationalism. What are the ethical limits to this vaccine nationalism? Neither extreme nationalism nor extreme cosmopolitanism is ethically justifiable. Instead, we propose the fair priority for residents (FPR) framework, in which governments can retain COVID-19 vaccine doses for their residents only to the extent that they are needed to maintain a noncrisis level of mortality while they are implementing reasonable public health interventions. Practically, a noncrisis level of mortality is that experienced during a bad influenza season, which society considers an acceptable background risk. Governments take action to limit mortality from influenza, but there is no emergency that includes severe lockdowns. This “flu-risk standard” is a nonarbitrary and generally accepted heuristic. Mortality above the flu-risk standard justifies greater governmental interventions, including retaining vaccines for a country's own citizens over global need. The precise level of vaccination needed to meet the flu-risk standard will depend upon empirical factors related to the pandemic. This links the ethical principles to the scientific data emerging from the emergency. Thus, the FPR framework recognizes that governments should prioritize procuring vaccines for their country when doing so is necessary to reduce mortality to noncrisis flu-like levels. But after that, a government is obligated to do its part to share vaccines to reduce risks of mortality for people in other countries. We consider and reject objections to the FPR framework based on a country: (1) having developed a vaccine, (2) raising taxes to pay for vaccine research and purchase, (3) wanting to eliminate economic and social burdens, and (4) being ineffective in combating COVID-19 through public health interventions.
We use three-dimensional (3-D) fully kinetic particle-in-cell simulations to study the occurrence of magnetic reconnection in a simulation of decaying turbulence created by anisotropic counter-propagating low-frequency Alfvén waves consistent with critical-balance theory. We observe the formation of small-scale current-density structures such as current filaments and current sheets as well as the formation of magnetic flux ropes as part of the turbulent cascade. The large magnetic structures present in the simulation domain retain the initial anisotropy while the small-scale structures produced by the turbulent cascade are less anisotropic. To quantify the occurrence of reconnection in our simulation domain, we develop a new set of indicators based on intensity thresholds to identify reconnection events in which both ions and electrons are heated and accelerated in 3-D particle-in-cell simulations. According to the application of these indicators, we identify the occurrence of reconnection events in the simulation domain and analyse one of these events in detail. The event is related to the reconnection of two flux ropes, and the associated ion and electron exhausts exhibit a complex 3-D structure. We study the profiles of plasma and magnetic-field fluctuations recorded along artificial-spacecraft trajectories passing near and through the reconnection region. Our results suggest the presence of particle heating and acceleration related to small-scale reconnection events within magnetic flux ropes produced by the anisotropic Alfvénic turbulent cascade in the solar wind. These events are related to current structures of the order of a few ion inertial lengths in size.
We use experimental methods to investigate subsidy incidence, the transfer of subsidy payments from intended recipients to other economic agents, in privately negotiated spot markets. Our results show that market outcomes in treatments with a subsidy given to either buyers or sellers are significantly different from both a no-subsidy treatment and the competitive prediction of a 50% subsidy incidence. The disparity in incidence across treatments relative to predicted levels suggests that incidence equivalence does not hold in this market setting. Moreover, we find no statistical difference in market outcomes when benefits are framed as a “subsidy” versus a schedule shift.
The Pueblo population of Chaco Canyon during the Bonito Phase (AD 800–1130) employed agricultural strategies and water-management systems to enhance food cultivation in this unpredictable environment. Scepticism concerning the timing and effectiveness of this system, however, remains common. Using optically stimulated luminescence dating of sediments and LiDAR imaging, the authors located Bonito Phase canal features at the far west end of the canyon. Additional ED-XRF and strontium isotope (87Sr/86Sr) analyses confirm the diversion of waters from multiple sources during Chaco’s occupation. The extent of this water-management system raises new questions about social organisation and the role of ritual in facilitating responses to environmental unpredictability.
We have a conundrum. The physical basis of information is clearly a highly active research area. Yet the power of information theory comes precisely from separating it from the detailed problems of building physical systems to perform information-processing tasks. Developments in quantum information over the last two decades seem to have undermined this separation, leading to suggestions that information is itself a physical entity and must be part of our physical theories, with resource-cost implications. We will consider a variety of ways in which physics seems to affect computation, but will ultimately argue to the contrary: rejecting the claims that information is physical provides a better basis for understanding the fertile relationship between information theory and physics. Instead, we will argue that the physical resource costs of information processing are to be understood through the need to consider physically embodied agents for whom information-processing tasks are performed. Doing so sheds light on what it takes for something to be implementing a computational or information-processing task of a given kind.
Field studies were conducted in 2007 and 2008 to evaluate fall applications of herbicides to control glyphosate-resistant (GR) horseweed before planting cotton. Fall treatments were compared with spring treatments for control of GR horseweed and effect on seed cotton yield. Fall and spring treatments with and without residual herbicides were also compared. No differences were observed for control of GR horseweed or seed cotton yield between fall and spring application timings. However, a difference was observed between fall applications with and without a residual herbicide. Fall applications that contained residual herbicides provided 86% control of GR horseweed and yielded 2,360 kg/ha of seed cotton. Fall applications that did not contain a residual herbicide only provided 70% control of GR horseweed and yielded 2,010 kg/ha of seed cotton. No benefit was observed from spring applications that contained a residual herbicide. This research indicates that glyphosate-resistant horseweed can be controlled with fall- or spring-applied burndown herbicides, and fall applications should include a residual herbicide for best results.
Managing glyphosate-resistant (GR) horseweed in no-till cotton continues to be a serious challenge for midsouthern producers. Field studies were conducted in 2008 and 2009 to evaluate spring burndown applications of saflufenacil on GR horseweed prior to planting cotton. Saflufenacil controlled GR horseweed at least 94% up to 7 d before planting (DBP) without causing significant cotton injury. Saflufenacil applied at 7 or 14 DBP controlled GR horseweed while still providing residual control until planting. Moreover, saflufenacil, on silt loam soil evaluated in this study, showed no more injury than dicamba applied 7 or more DBP. Results indicated that saflufenacil is an option in cotton for controlling GR horseweed much closer to cotton planting than 42 DBP (current saflufenacil label). At 25 g ha−1, which is the standard labeled rate in cotton, saflufenacil provided > 90% control of GR horseweed. Saflufenacil as a GR horseweed burndown, could replace the current dicamba standard every other year to reduce the probability of horseweed developing resistance to dicamba or salflufenacil.
A Research Committee was established by the Weed Science Society of America to outline the direction of weed science research during the next decade. Weeds adversely affect humans in both agricultural and nonagricultural environments. It is the opinion of the research committee that weed science will be advantageously positioned for the future if research focuses on research decision processes, weed biology and ecology, weed control and management practices, herbicide resistance, issues related to transgenic plants, environmental issues, and potential benefits of weeds. These future weed science research directions endorse those of the commodity and grower input group Coalition for Research on Plant Systems (CROPS)'99, a U.S. Department of Agriculture (USDA)-supported initiative. The future of weed science is dependent on a joint effort from industry, government regulators, and the public sector consisting of grower groups, as well as USDA, Agriculture and Agri-Food Canada (AAFC), and university researchers. It is our opinion that efforts spent on these research areas will benefit not only growers, commodity groups, homeowners, and industry, but society at large, through the maintenance and improvement of the food and fiber production system, and the environment in North America.
Nano-inkjet printing using an Electrohydrodynamic's (EHD) pulsed cone-jet approach has the potential to bring affordable additive manufacturing to the micro and nanoscale. Ink technology is a major limitation of current EHD techniques. Specifically, most EHD printing processes print either nanoparticles or polymers. The materials are structurally weak and often have poor electrical or mechanical properties. For example, printing nanoparticles effectively creates a cluster of nanoparticles that must be sintered to create a continuous material. To address these issues, we have been adapting reactive inks to work with an EHD pulsed cone-jet. Specifically, we demonstrate that silver micron-scale structures can be printed using an EHD pulsed cone-jet regime. These inks produce solid structures without sintering steps and with good electrical properties.1,2 This work shows that reactive ink chemistries can be combined with EHD printing to produce fine-resolution features consisting of solid metal without an annealing step.
Fabrication methods and performance characteristics of spiral stretchable interconnects fabricated using drop-on-demand printing of silver reactive inks are discussed. This work details ink optimization, device fabrication, and device characterization while demonstrating the potential applications for reactive inks and new design strategies in stretchable electronics. Devices were printed with an ethanol stabilized silver diamine reactive ink and cycled to 160 % over 100 cycles with less than 10% increase in electrical resistance. Maximum deformation before failure was measured at 180% elongation. A novel method for fabrication of a stretchable electronics device has been studied and verified.